1. Technical Field of the Invention
The present invention generally relates to network interfaces and means for internal communication and control within network interfaces.
2. Description of the Related Art
Network interfaces for connecting a device, such as a computer, to a network, commonly include a media access controller (MAC). The MAC ensures that data being sent is properly formatted and addressed frames or packets, so that the frames or packets are properly recognized by other computers on the network. Signals from the MAC are sent to a physical layer (PHY) which handles the actual transmission of signals on the network medium. The network medium may be any of a variety of well known media, such as fiber-optic cables or various types of dedicated metal-wire cables such as twisted shielded pair, 10 BASE-T, and wiring for telephone lines. Alternatively, the network medium may include wireless communication.
Software drivers are used to facilitate communication between the MAC and operating systems or application programs on the computer. Such device drivers translate the functions desired by the operating system or applications program into a form usable by the MAC. Such software device drivers are generally device specific, that is, a device driver for use with one MAC may often not be usable with a differently-designed MAC.
At times it may be desirable to incorporate a new physical layer device into a network interface card or other network interface which already contains a MAC. For example, it may be desirable to take a card or system having a MAC and PHY for connecting to one type of network medium, and modify it to be able to connect to an additional type or types of network media. A new device driver may be written to control such a hybrid system. However, writing new device drivers for each type of existing MAC involves considerable effort and expense.
From the foregoing it will be understood that it would be desirable to have improved means of making network interfaces utilizing existing MACs.